Utility functions

Utility functions help inspect storage and control the running engine.

Function	Result
format_bytes	A byte count formatted as text.
drop_cache	Number of cache entries evicted.

format_bytes

format_bytes(bytes)

Accepts an integer byte count and returns a VARCHAR using binary units, such as KiB and MiB. One KiB is 1024 bytes.

SELECT format_bytes(bytes) AS size
FROM (VALUES (1536::BIGINT)) AS input(bytes);
-- size: 1.5 KiB

Use it with system metadata:

SELECT name, format_bytes(bytes) AS size
FROM system.tables
ORDER BY bytes DESC;

drop_cache()

Takes no arguments. Clears Pivot’s caches, including compressed and decompressed data. Returns a BIGINT count of entries evicted.

SELECT drop_cache() AS entries_dropped;

The result depends on the cache contents at the time of the call.